466K views · 1.5K shares | The rainforest's version of the front-facing camera. | National Geographic Animals | Facebook

Our list of animals that pass the mirror test now mentions promising candidates: manta rays! http://bit.ly/1D1SnZO "The rays would repeatedly swim in front of the mirror, turning over to show their undersides and moving their fins. When in front of the mirror, they even blew bubbles, an unusual behavior. What the rays didn’t do is try to socially interact with the mirror image. All of this suggests that the rays might recognize it’s themselves they’re seeing in the mirror, not another ray. Howev

Tollen’s Test (Silver Mirror) Description: An aldehyde is oxidized by silver (I) to generate a carboxylic acid and silver metal, which coats the surface of the glass vessel. Materials: 0.1 M AgNO3 0.8 M KOH 0.5 M Dextrose Large test tube/rubber stopper Conc. HNO3 Beaker Conc. NH4OH Deionized water Procedure: This demonstration is best performed using a document camera. 1. Clean the test tube to be used by rinsing with concentrated nitric acid and washing well with hot water. 2. Prepare Tollen’s